• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2008.10b
• /
• pp.449-454
• /
• 2008

Finding an energy efficient route is one of the very important issues in the wireless sensor networks. The route scheme should consider both of the energy level of sensor nodes and the number of hops at the same time. First of all, this paper proposes an optimum routes finding scheme (ORFS), which could be used in the sensor network routing protocols. The scheme uses an optimum value for the path with the considerations of both the minimum energy level of a path and the number of hops at the same time. After that, this paper proposes a routing protocol based on the ORFS for how it could be used for the multipath directed diffusion with data aggregation (MDD-A), to get the better energy efficiency. The analysis result shows that the proposed routing protocol could lengthen the network life cycle about 18.7% compared to the previous MDD-A related protocols.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.12A
• /
• pp.1320-1328
• /
• 2007

In recent year, the popularity of WLAN has generated much interests on improvement and performance analysis of the IEEE 802.11 protocol. In this paper, we analyze two medium access methods of the IEEE 802.11 MAC protocol by investigating the MAC layer packet service times when arrival packet sizes have a general probability distribution. We use the M/G/1/K queueing model to analyze the throughput and the delay performance of IEEE 802.11 MAC protocol in a wireless LAN. We compare the performances of Basic access method and RTS/CTS access method. We take some numerical examples for the system throughput and the queue dynamics including the mean packet delay and packet blocking probability.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.6C
• /
• pp.593-600
• /
• 2005

Recently, RFID system is a main technology to realize ubiquitous computing environments. Because RFID system that is an automatic identification technology using radio frequency is a system to read and write the data of the entity. Therefore, many companies are interested in RFID system to reduce supply chain management and inventory control cost. However, for providing secure service, RFID authentication technology secure against tracking by an adversary is researched first. In this paper, we proposed security level based RFID authentication protocol providing reduce computational and communicational workload in the back-end database. The proposed protocol is secure against reply attack, spoofing attack, traffic analysis, and location privacy, since the proposed protocol based on the security of the hash function.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.8
• /
• pp.1674-1683
• /
• 2003

The performance of a packet data multiplexer with stop­and­wait ARQ protocols under Markovian interruption is considered in this work It is assumed that the input process, into the system is Poisson process, and that the output channel is divided into a series of time slots and a data packet can be transmitted in a slot time. In this system the round­trip propagation delay is defined to be the frame time. It is modeled that the output channel can be blocked by some Markevian interruption, whose state change between the blocking and non­-blocking states is given by Markov process. The overall system has been analyzed by constructing a relationship, taking the Markovian interruption into account, about the buffer behavior between the successive frames of slots. The validity of this analytical results has been verified by computer simulation.

• The KIPS Transactions:PartC
• /
• v.9C no.6
• /
• pp.817-822
• /
• 2002

We want to find a timestamping method which improves efficient performance and have high-level security to send secured messages in the digital signature and the law of e-commerces. Our paper shows a H-binary tree of time stamp to use a time stamp protocol with high suity and performance in the packets of sending messages. We implement and analyze the protocols, show to compare with previous RSA methods. Our proposed protocol has O(log n) time complexity and high-performance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.6
• /
• pp.1070-1075
• /
• 2006

TETRA system provides the radio authentication service which permits only authorized radio to access network. Radio authentication is the process which checks the sameness of authentication-key(K) shared between radio and authentication center by challenge-response protocol. TETRA standard authentication protocol can prevent the clone radio to copy ISSI from accessing network, but can't prevent the clone radio to copy ISSI & authentication-key. This paper analyzes authentication-key generation/delivery/infection model in TETRA authentication system and analyzes the threat of clone radio caused by authentication-key exposure. Finally we propose the new authentication protocol which prevent the clone radio to copy ISSI & authentication-key from accessing network.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.2 no.2
• /
• pp.117-130
• /
• 1999

In this paper, the performance of data communication function of military radio equipment P-999K is analyzed based on the standard CSMA/CA protocol which is DFWMAC standard protocol done by IEEE802.11 work group. Basic three standard protocols, i.e. Basic CSMA/CA, Stop & Wait ARQ and 4-Way Handshake CSMA/CA protocols are analyzed and compared with each other under the hidden terminal environment. The computer simulation is also done by using SIMSCRIPT II.5 which is popular software tool for an independent processing. The results show that p-persistent(with p=0.3) CSMA scheme is superior to non-persistent CSMA scheme with non-hidden terminal condition, but the performances of both schemes are almost same with hidden terminal situation. And the results of computer simulations are also showed that Basic CSMA/CA protocol is superior to the other protocols when the ratio of hidden terminals is below 10 % of total user population, however, with the above 20% hidden terminals environment and the higher offered traffic conditions the 4-Way Handshake CSMA/CA protocol shows the most superior performance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.2
• /
• pp.357-364
• /
• 2015

Tags and Readers is receiving and sending the data using the wireless communication in the RFID environment. Therefore, it could allow an attacker to participate in the network without the physical constraints, which can be easily exposed to a variety of attacks, such as taps and data forgery. Also, it is not easy to apply the security techniques to defend external attacks because the resource constraints of RFID tags is high. In this paper, new tag-reader mutual authentication protocol is proposed to protect the external cyber attacks such as spoofing attacks, replay attacks, traffic analysis attacks, location tracking attacks. The performance evaluation of the proposed mutual authentication protocol is performed and the simulation results are presented.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.2
• /
• pp.1388-1397
• /
• 2015

Recently, an application business model was proposed to implement an M-coupon system using the NFC-based mobile devices. In this paper, the security requirements were surveyed for a secure M-coupon system and to analyze the threats on the existing NFC-based M-coupon protocols. After considering the implementation efficiency and security, this paper presents a novel M-coupon protocol based on the Diffie-Hellman key agreement scheme. This protocol can be an alternative to solve the security problems related to the PKI (Public Key Infrastructure) and secret key distribution. Furthermore, this M-coupon protocol is designed to provide user authentication and counteract the relay attack.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.8
• /
• pp.2849-2864
• /
• 2021

The emerging of cloud data sharing can create great values, especially in multi-cloud environments. However, "data island" between different cloud service providers (CSPs) has drawn trust problem in data sharing, causing contradictions with the increasing sharing need of cloud data users. And how to ensure the data value for both data owner and data user before sharing, is another challenge limiting massive data sharing in the multi-cloud environments. To solve the problems above, we propose a Uniform Encoding and Parsing Framework (UEPF) with blockchain to support trustworthy and valuable data sharing. We design namespace-based unique identifier pair to support data description corresponding with data in multi-cloud, and build a blockchain-based data encoding protocol to manage the metadata with identifier pair in the blockchain ledger. To share data in multi-cloud, we build a data parsing protocol with smart contract to query and get the sharing cloud data efficiently. We also build identifier updating protocol to satisfy the dynamicity of data, and data check protocol to ensure the validity of data. Theoretical analysis and experiment results show that UEPF is pretty efficient.